Warp knitting machine mechanism

ABSTRACT

The yarn guide of a warp knitting machine is mounted for reciprocation through a first phase wherein the path of the yarn from the fixed supply cone to the yarn guide is shortened and a second phase wherein this path is lengthened. A mechanism is arranged in this path which comprises a yarn hook mounted for coordinated movement so that a stored length of the yarn is formed during the first phase and the stored length of yarn disappears during the second phase of the movement.

United States Patent 1 Bergmann 1 Juiy 17, 1973 WARP KNITTING MACHINEMECHANISM [75] Inventor: Gerhard Bergmann, Hausen,

Germany [73] Assignee: Karl Mayer Textilmaschinentghrik G.m.b.II.,Obertshausen, Germany 22 Filed: Dec. 6, 1971 211 App]. No.: 204,934

[30] Foreign Application Priority Data Dec. 12, 1970 Germany P 20 61343.8

[52] U.S. Cl 66/86, 66/84, 66/125 [51] Int. Cl D04b 23/00 [58] Field ofSearch 66/125, 126, 84, j I 7 66/83, 86, 64, 61

[561 References Cited i v UNITED STATES PATENTS 9/1972 Jeffcoat 66/125Licbrandt 66/86 X Lindley 66/84 FOREIGN PATENTS OR APPLICATIONS1,007,935 5/1957 Germany 66/146 Primary ExaminerRonald FeldbaumAttorney-Kurt Kelman [57] ABSTRACT The yarn guide of a warp knittingmachine is mounted for reciprocation through a first phase wherein thepath of the yarn from the fixed supply cone to the yarn guide isshortened and a second phase wherein this path is lengthened. Amechanism is arranged in this path which comprises a yarn hook mountedfor coordinated movement so that a stored length of the yarn is formedduring the first phase and the stored length of yarn disappears duringthe second phase of the movement.

4 Claims, 3 Drawing Figures PAIENIEU U I 71915 3. 745 792 sum 2 OF 2WARP KNITTING MACHINE MECHANISM The present invention relates to amechanism for forming a stored length of warp yarn in the path of theyarn from a fixedly mounted yarn cone to a yarn guide of a warp knittingmachine.

In known warp knitting machines, the yarn guide may be mounted forreciprocation through a first phase wherein the yarn guide is movedtowards the cone so that the path of the yarn between the cone and theyarn guide is shortened and a second phase wherein the yarn guide ismoved away from the cone so that the path of the yarn between the coneand the yarn guide is lengthened.

In machines of this type, the rotary speed of the main shaft, whichcontrols the speed of the knitting cycles in a well known manner, islimited by the maximum speed of delivery of the warp yarn from its fixedsupply, i.e., a yarn storage cone or spool, to the yarn guide which laysthe yarn into the knitting needles during the knitting cycles. Duringeach half cycle, the yarn is accelerated by the guide from standstill toa maximum speed and then decelerated again to standstill. At its maximumspeed, the yarn is subjected to a maximum tension which is limited bythe tensile strength or limit of extensibility of the yarn. Since thelatter is rather low in the case of low-denier yarns in particular, themaximal machine speed obtainable cannot, in fact, be used.

While efforts have been made to equalize the tension of the yarn bystoring a length of the yarn in its path from the cone to the yarnguide, they have not been successful because they failed to take intoaccount the phased acceleration and deceleration of the yarn describedhereinabove.

It is the primary object of this invention to provide an improvedmechanism for forming a stored length of warp yarn in its path to theyarn guide of a warp knitting machine by equalizing the speed of theyarn throughout all phases of its movement.

The above and other objects are accomplished in accordance with theinvention with a mechanism which comprises a yarn engaging devicemounted for movement in coordination with the movement of the main yarnguide of the warp knitting machine and engaging the yarn in its pathfrom a fixedly mounted yarn cone to the main yarn guide. The movementsof the main yarn guide and the yarn engaging device are so coordinatedthat a stored length of theyarn is formed during the first phase of themain yarn guide reciprocation and the stored length of yarn is taken upor disappears during the second phase of the reciprocatory movement ofthe main yarn guide.

In this manner, the speed of drawing the yarn off the cone is maintainedsubstantially constant, i.e. there is no yarn standstill and resultantyarn breakages at the points where the main yarn guide reverses itscourse during reciprocation.

In a preferred embodiment, the yarn engaging device is arranged todeflect the yarn in its path to form the stored length of yarn, forinstance by mounting an auxiliary yarn guide for reciprocation parallelto the reciprocatory movement of the main yarn guide and spacedtherefrom. The movements of the yarn guides are so coordinated that theauxiliary yarn guide precedes the main yarn guide in the direction oftheir movements.

' Advantageously, the auxiliary yam guide has a hookshaped yarnsengaging member, and an endless moving chain carries the yarn guide.

The above and other objects, advantages and fea' tures of the presentinvention will be more fully understood by reference to the followingdetailed description of two now preferred embodiments thereof, taken inconjunction with the accompanying drawing wherein FIG. I is a schematicperspective view showing the essential parts of one embodiment of theapparatus of this invention:

FIG. 2 is a side view of another embodiment of the apparatus, againlimited to a schematic showing of the essential portions differing fromthose in the one embodiment; and

FIG. 3 shows a detail of the apparatus.

Referring now to the drawing, wherein like reference numerals designatelike parts functioning in a like manner in all figures, FIG. I shows awarp yarn guiding mechanism in a warp knitting machine according to oneembodiment of the present invention, the knitting machine beingotherwise conventional and, therefore, not illustrated.

As schematically illustrated, a plurality of knitting needles 4 areembedded in lead 3, the knitting needles being arranged in a straightarray in the needle bed. A main yarn guide I is arranged forreciprocating movement parallel to the arrayed needles 4%. For thispurpose, the yarn guide I is glidingly mounted on a pair of guide rods5, 5 extending parallel to the needle bed 3, the yarn guide beingattached to, and driven by, a cable 6 which is trained over guide pulley'7 and drive pulley 8. The drive pulley is keyed to rotary shaft 9 whichhas affixed thereto main gear III. The main gear meshes with ratchet IIwhose lower end is linked to one end of connecting rod I I whose otherend is linked to crank 17 of main crank drive 13. The crank drive iscoupled to the cam shaft 15 of the warp knitting machine by means ofbeveled gear transmission M. The machine shaft I5 controls the knittingmechanisms of the warp knitting machine in a known manner, its constantrotation being transmitted to the crank drive I3 by transmission 14 tocrank the connecting rod I2. and thus to reciprocate the ratchet IIvertically. This, in turn, causes rotary reciprocation of drive pulley band the corresponding reciprocation of the yarn guide I in relation tothe knitting needles t since cable 6 is driven by pulley 8 and isaffixed to the yarn guide.

An auxiliary yarn guide I6 is mounted in the illustrated embodimentbehind main yarn guide I and the warp yarn is also threaded through theauxiliary guide to form a stored length of the yarn during the operationof the mechanism. If desirable, the auxiliary yarn guide may also bemounted above or below the main yarn guide, instead of being arrangedbehind it.

The guidance and drive system for the auxiliary yarn guide Rh issubstantially a duplicate of the guidance and drive system for main yarnguide 1. It also includes a pair of guide rods 5a, 5a whereon the yarnguide I6 is glidingly mounted for parallel movement to yarn guide I. Thecable drive 60 is also actuated by the drive pul ley of the cable drivebeing keyed to rotary shaft 9, with an auxiliary gear 10:: on the shaftmeshing with ratchet IIa which is connected to, and driven by, crank I7aof auxiliary crank drive Ida. As shown in FIG. I, the auxiliary crank17a is angularly offset from main crank I7 so that, during the constantrotation of shaft 9, the auxiliary yarn guide I6 always is spaced from,and precedes, the main yarn guide I in the direction of the needlearray.

FIGS. 2 and 3 show preferred features of such a warp yarn guidemechanism. In this embodiment, the auxiliary yarn guide 160 comprises ahook l9 and is affixed to an endless chain 18 which is trained about twopulleys and is constantly driven so that the hook 16a continuously movesfirst in one direction and then in the reverse direction about thepulleys. Such an auxiliary yarn guide drive is considerably simpler instructure and may be readily operated or switched out of operationaccording to the pattern requirements.

The auxiliary yarn guide, for instance the book 19 which is open at oneside, seizes the warp yarn and, since it precedes the main yarn guide 1,or has a lead over it, produces a stored length of yarn. If a certainpattern requires omission of a warp yarn, a conventional device foreither laying the yarn into the knitting needles or preventing the sameis associated with the main yarn guide, such means forming no part ofthe present invention and not being illustrated. When such meansinterrupts the laying of. the yarn in the knitting needles, means isprovided according to a preferred feature of the invention to preventthe hook 19 from seizing the yarn and thus to form a stored length ofyarn. For this purpose, a yarn deflector 20 is mounted between the yarnstorage cone (not shown) and the main yarn guide 1, the deflector beingmovable between an inoperative position 20a (shown in broken lines inFIG. 3) outside the path 2a of the yarn from the main to the auxiliaryyarn guide and an operative position wherein the deflector extends intothe path of yarn 2 to deflect the yarn and thus move it out ofengagement with the auxiliary yarn guide hook 19, as shown in full linesin FIG. 3. The pivotal deflector 20 is operatively coupled with thepatterning means which interrupts the laying of the yarn in the knittingneedles so that it will be moved into and out of its operative positionin response to the respective movements of this means.

When the deflector is in its inoperative or rest position 200, the path2a of the yarn leads directly from the main yarn guide to the auxiliaryyarn guide so that the mechanism of the present invention is in itsoperative position. In its operative position, the deflector 20 deflectsyarn 2 sufficiently to lift it off the auxiliary guide so that themechanism of this invention becomes inoperative.

The mechanism operates as follows when deflector 20 is in itsinoperative position:

The warp yarn 2 is supplied to the warp knitting machine from a fixedcone 22 or spool whence it would normally move in a straight path to theyarn guide 1 of the machine as the same is reciprocated passed the arrayof knitting needles 4 and parallel thereto in a first phase wherein theyarn guide is moved towards the cone C so that the path of the yarnbetween cone and guide is shortened and in a second phase wherein theyarn guide is moved away from the cone so that its path is lengthened.

According to the invention, an auxiliary yarn guide 16, 16a is arrangedin the yarn path between the cone and the main yarn guide 1, and sincethe auxiliary yarn guide precedes the main yarn guide during itsreciprocatory movement, it will provide an extra length of yarn in thispath during the first phase of the movement so as to form a storedlength of yarn while this stored length of yarn will disappear duringthe second phase of the movement.

I claim:

1. A mechanism for forming a stored length of warp yarn in the path ofthe yarn from a fixedly mounted yarn cone to a main yarn guide of a warpknitting machine, the main yarn guide being mounted for reciprocationthrough a first phase wherein the main yarn guide is moved towards thecone so that the path of the yarn between the cone and the main yarnguide is shortened and a second phase wherein the yarn guide is movedaway from the cone so that the path of the yarn between the cone and theyarn guide is lengthened, the mechanism comprising an auxiliary yarnguide mounted for reciprocation parallel to the reciprocatory movementof the main yarn guide and spaced therefrom, the auxiliary yarn guideengaging the yarn in said path, the movements of the yarn guides beingso coordinated that the auxiliary yarn guide precedes the main yarnguide in the direction of their movements.

2. The mechanism of claim 1, wherein the auxiliary yam guide is arrangedto deflect the yarn in said path.

3. The mechanism of claim 1, wherein the auxiliary yarn guide has ahook-shaped yarn engaging member, and further comprising an endlessmoving chain carrying the auxiliary yarn guide.

4. The mechanism of claim 3, further comprising a deflector mounted forpivotal movement from an inoperative position outside the path of theyarn between the auxiliary yarn guide and the main yarn guide, and anoperative position wherein the deflector extends into said path todeflect the yarn and thus move it out of engagement with the hook-shapedyarn engaging member.

1. A mechanism for forming a stored length of warp yarn in the path ofthe yarn from a fixedly mounted yarn cone to a main yarn guide of a warpknitting machine, the main yarn guide being mounted for reciprocationthrough a first phase wherein the main yarn guide is moved towards thecone so that the path of the yarn between the cone and the main yarnguide is shortened and a second phase wherein the yarn guide is movedaway from the cone so that the path of the yarn between the cone and theyarn guide is lengthened, the mechanism comprising an auxiliary yarnguide mounted for reciprocation parallel to the reciprocatory movementof the main yarn gUide and spaced therefrom, the auxiliary yarn guideengaging the yarn in said path, the movements of the yarn guides beingso coordinated that the auxiliary yarn guide precedes the main yarnguide in the direction of their movements.
 2. The mechanism of claim 1,wherein the auxiliary yarn guide is arranged to deflect the yarn in saidpath.
 3. The mechanism of claim 1, wherein the auxiliary yarn guide hasa hook-shaped yarn engaging member, and further comprising an endlessmoving chain carrying the auxiliary yarn guide.
 4. The mechanism ofclaim 3, further comprising a deflector mounted for pivotal movementfrom an inoperative position outside the path of the yarn between theauxiliary yarn guide and the main yarn guide, and an operative positionwherein the deflector extends into said path to deflect the yarn andthus move it out of engagement with the hook-shaped yarn engagingmember.